The stunned 47-year-old said: “When I realised what I’d found, I couldn’t speak. I was in complete shock. The detector made a signal I should never have heard as the find was so deep.

“I started to dig but I thought it would just be a cast-iron pipe.

“I put my hand in the hole and felt what I thought was a heavy silver spoon but, when I rubbed it with my thumb and saw the criss-cross design, I realised it was Viking.”

SWNS Group

A large silver alloy Carolingian lidded vessel

Within hours, experts from Historic Scotland had arrived at the field in Dumfries and Galloway to begun a major excavation of the site.

The haul also includes a medieval Christian cross, silver and gold jewellery, glass beads, rare Viking arm rings and possibly the largest silver Carolingian pot ever discovered - with its lid still in place.

The pot is likely to have been around 100 years old when the hoard was buried in the mid 9th or 10th Centuries.

A solid silver cross - which has enamelled decorations which experts consider to be highly unusual - was also amongst the collection.

SWNS Group

An early medieval cross

Derek’s find has still be formally valued, but experts have suggested it could be into seven figures.

And it comes after lucky Derek hit the headlines earlier this year after discovering 322 medieval coins in a field near Kirkcudbright.

His latest find is thought to be around 1000 years old.

Derek and the landowner can expect to share in the massive payout once Government body, the Treasure Trove Unit, have it valued.

Head of the unit, Stuart Campbell, said it was “a hugely significant find which will interest scholars from all over the world”.